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Brinkman P 《Endeavour》2006,30(4):126-130
Thin at one end, thicker in the middle, then thin again at the other end, Brontosaurus is one of the most famous dinosaurs. So why do paleontologists call it Apatosaurus? Othniel Charles Marsh coined both names from two relatively complete specimens in the late 1870s. Additional specimens collected during the second American Jurassic dinosaur rush (1895-1905) provided the material for revisions. Henry Fairfield Osborn, who detested Marsh, systematically sought to overturn his work. Yet it was Elmer Samuel Riggs who showed that Marsh's Apatosaurus and Brontosaurus are synonymous, and Osborn who stubbornly, and inexplicably, adhered to the latter. 相似文献
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The effects of economic conditions upon higher education enrollments are specified nationally, regionally, and for an individual institution. It appears clear that since the early 1970s, about the time when studies began to report on the declining value of a college education, and when nontraditional students became a more significant factor in overall enrollments, potential students became much more sensitive to the opportunity costs of college attendance. As job opportunities increased, foregone earnings grew correspondingly, and enrollments turned down. Economic reversals were accompanied by enrollment upturns. Implications of this study for enrollment projections and planning are clear. 相似文献
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Paul T. Brinkman 《Research in higher education》1985,23(2):201-218
Ordinary least squares regression (OLS) is often used to estimate the relationship between cost and enrollment. Cost is normally regarded as being a function of enrollment, and the regression equation is structured accordingly. If, however, enrollment is also a function of cost, which some have suggested, then OLS estimates will be biased and inconsistent. The problem is known as simultaneous-equation bias. This study addresses the materiality of this threat in a representative higher-education context. A model is constructed in which it is assumed that cost and enrollment at public two-year colleges are mutually influential. The model is then estimated by both OLS and two-stage least squares regression. The results differ only slightly. This suggests that the prudent use of OLS in similar situations need not be proscribed. 相似文献
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Twenty years after the statements of Ausubel, much research has been done on pupils’ ideas but little has been done on strategies that make use of these ideas in teaching, especially in biology education. Moreover little research, up until now, concentrates on concepts regarding Environmental Education. For Environmental Education the concepts of Cycles and Health are important. In this paper pupils’ ideas on these concepts are assessed and represented and common pupil ideas between the two concepts are discussed. A teaching strategy based upon pupils’ ideas is elaborated. 相似文献